Topical antibiotic composition for the prevention of Lyme disease

ABSTRACT

The invention relates to topical pharmaceutical compositions and methods related to  Borrelia burgdorferi  toxins, in particular, the present invention provides compositions and methods for the treatment of infections caused by  Borrelia burgdorferi  and in particular for the prevention of Lyme disease.

FIELD OF THE INVENTION

The invention relates to topical pharmaceutical compositions and methodsrelated to Borrelia burgdorferi toxins, in particular, the presentinvention provides compositions and methods for the treatment ofinfections caused by Borrelia burgdorferi and in particular for theprevention of Lyme disease.

BACKGROUND OF THE INVENTION

Lyme disease is a potentially severe and complex multisystem disorderassociated with the tick-borne Borrelia burgdorferi toxins. The diseaseis transmitted to humans and other animals through arthropod bites. TheBorrelia species are maintained in nature by cycling through the wildanimals (e.g., deer, rodents and fowl) and the ticks that feed uponthem. Lyme disease was first officially recognized in North America in1975, and has become recognized as the most prevalent tick-borne diseasein the U.S. This recognition was due to an outbreak of disease inchildren in Lyme, Conn. The disease is now recognized as having aworldwide distribution.

In the northeastern United States, Wisconsin and Minnesota, the deertick, Ixodes dammini is the primary vector, while in the western UnitedStates and Europe, I. pacifious and I. ricinus are the main vectors,respectively.

The clinical symptoms of Lyme disease vary among individuals and duringthe time course of infection, and range from a relatively benign skinrash to severe arthritic, neurologic and cardiac manifestations. Themost common clinical manifestation is the distinctive skin rash(“erythema migrans,” “erythema chronicam migrans,” or “ECM”) whichfollows the bite of an infected tick. This rash is often accompanied byheadache, stiff neck, myalgias, arthralgias, malaise, fatigue, and/orlymph node swelling. Weeks to months later, some infected patientsdevelop meningoencephalitis, myocarditis, or migrating musculoskeletalpain. Even later in the course of disease, patients may experienceintermittent attacks of oligoarticular arthritis or chronic arthritis inlarge joints, particularly in the knee. Other clinical syndromes arereported that may have the same etiologic agent include lymphocytoma(lymphadenosis benigna cutis), acro-dermalitis chronica atrophicans,tick-borne meningoradiculitis (Garin-Bujadoux-Bannwarth's syndrome), andmyositis. Due to increased awareness and reporting, reported cases ofLyme disease have increased over time. Between 1982 and 1992,approximately 50,000 cases of Lyme disease were reported to the Centersfor Disease Control (CDC), with 48 states reporting cases by 1992.

When the risk of Lyme disease is great, oral antibiotics are frequentlyadministered to people who have been bitten by ticks. However, liberaloral administration of antibiotics is controversial and the risk ofinfection has to be balanced against indiscriminate long-term treatmentwith antibiotics. As an alternative, the topical application of certainantibiotics (Chien-Ming Shih and Andrew Spielman, “Topical Prophylaxisfor Lyme Disease after Tick Bite in a Rodent Model”, The Journal ofInfectious Diseases, 1993, 168, p. 1042-1045) was evaluated and it couldbe shown that in a rodent model local infection was not detectable aftersuch treatment. These studies further demonstrated, that by means ofXenodiagnosis, no B. burgdorferi were detected 28 days after the tickfeeding. These findings, however, make no conclusive statement whetherthe transfer of B. burgdorferi from the site of infection to Borrelia'starget organs can be effectively be prevented.

B. burgdorferi is presenting several morphological forms with differentsensitivity to antibiotics and environmental stress, such as exposure todistilled water or freeze-thaw cycles. Cystic forms (also calledspheroplasts or starvation forms) have the ability to reconvert intonormal motile spirochetes both in vitro and in vivo [Brorson O. et al.,Infection. 1997 July-August; 25(4):240-6]. The presence of variousatypical spirochete forms: spheroplastic L (without cell walls), cystic,and granular “blebs” has also been reported. One may thereforedistinguish spirochetal forms, which are linked with high metabolic andproliferative activity, from cystic and spherical forms, which aredormant with minimal biochemical activity.

In view of debilitating nature of the advanced stages of the disease,compositions and methods for disease prevention remain critical.However, these needs have not previously been satisfactorily met.

DETAILED DESCRIPTION OF THE INVENTION

It has now surprisingly been found that a topical application of anantibiotic administered to the site of a tick bite prevents an infectionby the Lyme disease. In order to prevent the infection of Lyme disease,it is essential that the Borrelia burgdorferi bacterium is eradicated inthe early stages of infection when the prevailing form is thespirochetal form. A rapid, sustained, and extensive penetration intointracellular and interstitial tissue compartments has therefore to beachieved as well as antibiotics used showing prolonged tissue and serumhalf-lives. Achieving high tissue concentration was also found necessaryto eradicate all forms of Borrelia burgdorferi including thosepresenting in cystic or spherical forms which would otherwise serve as areservoir for a new outbreak of Lyme disease.

The studies underlying the present invention demonstrate, that the newcomposition presented here with an antibiotic effectively removes B.burgdorferi at the site of tick-feed and, furthermore and unexpectedly,from tissues/organs in which B. burgdorferi persist. This finding isparticularly important, as it has been found that B. burgdorferipreferentially persist in these tissues/organs, rather than thecirculation only. These findings are particularly important for targettissues of Borrelia, such as heart, bladder, joints and ear. Only iferadication of B. burgdorferi from these tissues can be demonstrated,the success of a treatment including a topical treatment administered tothe site of tick-feed can be guaranteed.

In the context of the present invention “Borrelia burgdorferi”encompasses the genospecies complex Borrelia burgdorferi sensu lato,particular examples being Borrelia afzelii, Borrelia garinii, Borreliaburgdorferi sensu stricto, Borrelia valaisiana, Borrelia spielmanii,Borrelia lusitaniae, Borrelia babesiosis and Borrelia erlichiosis. Thepresent invention in particular relates to Borrelia burgdorferi sensustricto.

In the context of the present invention “Lyme disease” encompasses Lymedisease and related diseases such as, for example, Southern TickAssociated Rash Illness (STARI) and Rocky Mountains spotted fever. Thepresent invention in particular relates to Lyme disease specifically.

A first aspect of the invention is the use of an antibiotic for thepreparation of a topical pharmaceutical composition for the preventionof Lyme disease.

A further aspect of the invention is the use of an antibiotic for thepreparation of a topical pharmaceutical composition for the eliminationof Borrelia burgdorferi resulting from a tick bite.

A further aspect of the invention is the use of an antibiotic for thepreparation of a topical pharmaceutical composition for the eliminationof spirochetal forms of Borrelia burgdorferi resulting from a tick bite.

A further aspect of the invention is the use of an antibiotic for thepreparation of a topical pharmaceutical composition for the eliminationof cystic and spherical forms of Borrelia burgdorferi resulting from atick bite.

A further aspect of the invention is the method for preventing Lymedisease comprising administering a therapeutically effective amount ofan antibiotic in the form of a topical pharmaceutical composition to thesite of the tick bite to a patient in need thereof.

A further aspect of the present invention is related to a topicalpharmaceutical composition, in particular for the prevention of Lymedisease or for the elimination of Borrelia burgdorferi (includingspirochetal, cystic and/or spherical forms) resulting from a tick bitecomprising an antibiotic, a volatile solvent (defined as water or asolvent more volatile than water) and, optionally, a solidifying agent.

The different aspects of the invention are described now in more detailwhereby the given examples and preferences apply to all of the aboveaspects unless otherwise stated.

For example, a suitable antibiotic is selected from rifamycin,penicillin G, penicillin V, methicillin, oxacillin, cloxacillin,dicloxacillin, nafcillin, ampicillin, amoxicillin, carbenicillin,ticarcillin, mezlocillin, piperacillin, azlocillin, temocillin,cepalothin, cephapirin, cephradine, cephaloridine, cefazolin,cefamandole, cefuroxime, cephalexin, cefprozil, cefaclor, loracarbef,cefoxitin, cefmatozole, cefotaxime, ceftizoxime, ceftriaxone,cefoperazone, ceftazidime, cefixime, cefpodoxime, ceftibuten, cefdinir,cefpirome, cefepime, BAL5788, BAL9141, imipenem, ertapenem, meropenem,astreonam, clavulanate, sulbactam, tazobactam, streptomycin, neomycin,kanamycin, paromycin, gentamicin, tobramycin, amikacin, netilmicin,spectinomycin, sisomicin, dibekalin, isepamicin, tetracycline,chlortetracycline, demeclocycline, minocycline, oxytetracycline,methacycline, doxycycline, erythromycin, azithromycin, clarithromycin,dirithromycin, roxithromycin, telithromycin, troleandomycin, ABT-773,lincomycin, clindamycin, vancomycin, oritavancin, dalbavancin,teicoplanin, quinupristin and dalfopristin, sulphanilamide,paraaminobenzoic acid, sulfadiazine, sulfisoxazole, sulfamethoxazole,sulfathalidine, linezolid, nalidixic acid, oxolinic acid, norfloxacin,perfloxacin, enoxacin, ofloxacin, ciprofloxacin, temafloxacin,lomefloxacin, fleroxacin, grepafloxacin, sparfloxacin, trovafloxacin,clinafloxacin, gatifloxacin, moxifloxacin, gemifloxacin, sitafloxacin,metronidazole, daptomycin, garenoxacin, ramoplanin, faropenem,polymyxin, tigecycline, AZD2563, and trimethoprim. Preferably, theantibiotic is selected from azithromycin, clarithromycin, dirithromycin,roxithromycin, telithromycin, troleandomycin, chlortetracycline,demeclocycline, minocycline, oxytetracycline and methacycline. Alsopreferred are antibiotics selected from the classes of macrolides andtetracyclines. Most preferably, the antibiotic is azithromycin. In afurther embodiment more than one antibiotic, for example twoantibiotics, may be present in the composition.

For most compositions, the weight percentage of the antibiotic can befrom about 1 wt % to about 30 wt %, preferably from about 3 wt % toabout 20 wt % and more preferably from about 7 wt % to about 20 wt %,based on the total weight of the composition. The weight percentage ofthe antibiotic is preferably at least 1 wt %, more preferably at least 3wt %, even more preferably at least 5 wt % and most preferably at least7 wt % based on the total weight of the composition. The weightpercentage of the antibiotic is preferably at most 30 wt %, morepreferably at most 20 wt % and most preferably at most 15 wt % based onthe total weight of the composition. Given the minimum and maximumamounts above, the weight percentage of the antibiotic is, for example,from 1 wt % to 20 wt % or from 3 wt % to 15 wt % based on the totalweight of the composition.

“Topical pharmaceutical composition” shall mean a pharmaceuticalcomposition delivering a therapeutically effective amount of theantibiotic to a skin tissue, and subsequent absorption into the skinthat may occur. Examples of such topical pharmaceutical compositions areliquids, lacquers, creams, pastes, gels, sprays, ointments, patches andvarnishes. In addition to said topical compositions in a strict sense,in connection with the instant invention, a topical pharmaceuticalcomposition also relates to compositions useful for subcutaneousinjection, application by scratching the skin (as for example known frompox vaccines), treatment in presence of an occlusive environment, e.g.as a result of a patch, a dressing or any chemical treatment precedingor succeeding or during the application of the therapeutic with the aimto enhance the topical delivery.

“Therapeutically effective amount” or the like, as it relates to a drug,refers to sufficient amounts or delivery rates of a drug which achievesany appreciable level of therapeutic results in treating a condition forwhich the drug is being delivered. It is understood that “appreciablelevel of therapeutic results” may or may not meet any governmentagencies' efficacy standards for approving the commercialization of aproduct. It is understood that various biological factors may affect theability of a substance to perform its intended task. Therefore, a“therapeutically effective amount” may be dependent in some instances onsuch biological factors to some degree. However, for each drug, there isusually a consensus among those skilled in the art on the range of dosesthat are sufficient in most subjects. Further, while the achievement oftherapeutic effects may be measured by a physician or other qualifiedmedical personnel using evaluations known in the art, it is recognizedthat individual variation and response to treatments may make theachievement of therapeutic effects a subjective decision. Thedetermination of a therapeutically effective amount or delivery rate iswell within the ordinary skill in the art of pharmaceutical sciences andmedicine.

Before application to the skin, the topical pharmaceutical compositionis in its initial, less-than-solid form, such as lacquer, liquid, cream,gel, paste or ointment. After applying a layer of such a composition onthe skin area to be treated, the evaporation of the volatile solvent(s),with the help from the solidifying agent, can convert the compositionlayer into a soft, flexible, coherent solid layer that is optionallypeelable. The soft, flexible, coherent solid layer is designed to adhereto the skin for a substantial duration, preferably longer than 30minutes.

The application viscosity of the topical pharmaceutical composition istypically more viscous than a water-like liquid, but less viscous than asoft solid. Examples of preferred viscosities include materials thathave consistencies similar to pastes, gels, ointments, and the like,e.g., viscous liquids that flow but are not subject to spilling. Thismeans the composition has a viscosity that is high enough so that thecomposition does not substantially run off the skin after being appliedto skin, but also has a low enough viscosity so that it can be easilyspread onto the skin.

In some embodiments of the present invention, it may be desirable to addan additional agent or substance to the topical pharmaceuticalcomposition so as to provide enhanced or increased adhesivecharacteristics. The additional adhesive agent or substance can be anadditional solidifying agent or a non-volatile solvent (defined as lessvolatile than water). The non-volatile solvent stays in the formulationfor substantially the entire duration of the application and serves asvehicle solvent for delivering the drug into the skin (a fraction of thenon-volatile solvent(s) may be absorbed by skin during the application).Non-limiting examples of substances which might be used as additionaladhesion enhancing agents include copolymers of methylvinyl ether andmaleic anhydride (Gantrez polymers), polyethylene glycol and polyvinylpyrrolidone, gelatin, low molecular weight polyisobutylene rubber and/orvarious aliphatic resins and aromatic resins.

In selecting the various components that can be used, e.g., antibiotic,volatile solvent(s) and solidifying agent(s), etc., many variations canbe considered.

For example, the volatile solvent may be one or more volatile solvents(at least as volatile as water, including water). In one embodiment ofthe present invention, the volatile solvent can include a member ofethanol, isopropyl alcohol, propanol, dimethylsulfoxid, dimethyl ether,diethyl ether, butane, propane, isobutene, ethyl acetate, acetone,water, or combinations thereof. In another embodiment of the presentinvention, the volatile solvent can include iso-amyl acetate, denaturedalcohol, methanol, propanol, isopropylalcohol, isobutene, pentane,hexane, chlorobutanol, turpentine, cytopentasiloxane, cyclomethicone,methyl ethyl ketone, or combinations thereof. The volatile solvent caninclude a mixture or combination of any of the volatile solvents setforth in the embodiments above. A preferred volatile solvent is ethanol,water or a combination thereof.

The volatile solvents should be chosen to be compatible with the rest ofthe formulation. It is desirable to use an appropriate weight percentageof the volatile solvent(s) in the formulation. Too much of the volatilesolvent system prolongs the drying time. Too little of the volatilesolvent system can make it difficult to spread the composition on theskin. For most compositions, the weight percentage of the volatilesolvent(s) can be from about 40 wt % to about 99 wt %, preferably fromabout 40 wt % to about 95 wt % and more preferably from about 50 wt % toabout 95 wt %, based on the total weight of the composition. In case ofa composition comprising only antibiotic and volatile solvent, theweight percentage of the volatile solvent(s) is at least 70 wt % basedon the total weight of the composition.

Non-volatile solvent(s) that can be used alone or in combination to formnon-volatile solvent systems can be selected from a variety ofpharmaceutically acceptable liquids. In one embodiment of the presentinvention, the non-volatile solvent system can include glycerol,propylene glycol, isostearic acid, oleic acid, propylene glycol,trolamine, tromethamine, triacetin, sorbitan monolaurate, sorbitanmonooleate, sorbitan monopalmitate, butanol, or combinations thereof. Inanother embodiment the non-volatile solvent system can include benzoicacid, butyl alcohol, dibutyl sebecate, diglycerides, dipropylene glycol,eugenol, fatty acids such as coconut oil, fish oil, palm oil, grape seedoil, isopropyl myristate, mineral oil, oleyl alcohol, vitamin E,triglycerides, sorbitan fatty acid surfactants, triethyl citrate, orcombinations thereof. In a further embodiment, the non-volatile solventsystem can include 1,2,6-hexanetriol, alkyltriols, alkyldiols, acetylmonoglycerides, tocopherol, alkyl dioxolanes, p-propenylanisole, aniseoil, apricot oil, dimethyl isosorbide, alkyl glucoside, benzyl alcohol,bees wax, benzyl benzoate, butylene glycol, caprylic/caprictriglyceride, caramel, cassia oil, castor oil, cinnamaldehyde, cinnamonoil, clove oil, coconut oil, cocoa butter, coco-glycerides, corianderoil, corn oil, coriander oil, corn syrup, cottonseed oil, cresol,cyclomethicone, diacetin, diacetylated monoglycerides, diethanolamine,diethylene glycol monoethyl ether, diglycerides, ethylene glycol,eucalyptus oil, fat, fatty alcohols, flavors, liquid sugars gingerextract, glycerin, high fructose corn syrup, hydrogenated castor oil, IPpalmitate, lemon oil, lime oil, limonene, milk, monoacetin,monoglycerides, nutmeg oil, octyldodecanol, olive alcohol, orange oil,palm oil, peanut oil, PEG vegetable oil, peppermint oil, petrolatum,phenol, pine needle oil, polypropylene glycol, sesame oil, spearmintoil, soybean oil, vegetable oil, vegetable shortening, vinyl acetate,wax, 2-(2-(octadecyloxy)ethoxy)ethanol, benzyl benzoate, butylatedhydroxyanisole, candelilla wax, carnauba wax, ceteareth-20, cetylalcohol, polyglyceryl, dipolyhydroxy stearate, PEG-7 hydrogenated castoroil, diethyl phthalate, diethyl sebacate, dimethicone, dimethylphthalate, PEG Fatty acid esters such as PEG-stearate, PEG-oleate,PEG-laurate, PEG fatty acid diesters such as PEG-dioleate,PEG-distearate, PEG-castor oil, glyceryl behenate, PEG glycerol fattyacid esters such as PEG glyceryl laurate, PEG glyceryl stearate, PEGglyceryl oleate, hexylene glycerol, lanolin, lauric diethanolamide,lauryl lactate, lauryl sulfate, medronic acid, methacrylic acid,multisterol extract, myristyl alcohol, neutral oil, PEG-octyl phenylether, PEG-alkyl ethers such as PEG-cetyl ether, PEG-stearyl ether,PEG-sorbitan fatty acid esters such as PEG-sorbitan diisosterate,PEG-sorbitan monostearate, propylene glycol fatty acid esters such aspropylene glycol stearate, propylene glycol, caprylate/caprate, sodiumpyrrolidone carboxylate, sorbitol, squalene, stear-o-wet, triglycerides,alkyl aryl polyether alcohols, polyoxyethylene derivatives ofsorbitan-ethers, saturated polyglycolyzed C8-C10 glycerides,N-methylpyrrolidone, honey, polyoxyethylated glycerides, dimethylsulfoxide, azone and related compounds, dimethylformamide, N-methylformamide, fatty acid esters, triglyceride oils, such as containingplant derived carylic/capric triglycerides (Miglyol 812), fatty alcoholethers, alkyl-amides (N,N-dimethylalkylamides), N-methylpyrrolidonerelated compounds, ethyl oleate, polyglycerized fatty acids, glycerolmonooleate, glycerol triacetate, glyceryl monomyristate, glycerol estersof fatty acids, silk amino acids, PPG-3 benzyl ether myristate, Di-PPG2myreth 10-adipate, honeyquat, sodium pyroglutamic acid, abyssinica oil,dimethicone, macadamia nut oil, limnanthes alba seed oil, cetearylalcohol, PEG-50 shea butter, shea butter, aloe vera juice, phenyltrimethicone, hydrolyzed wheat protein, or combinations thereof. In yeta further embodiment the non-volatile solvent system can include acombination or mixture of non-volatile solvents set forth above. Onefurther benefit of the mixing of the non-volatile solvents is that itmay optimize the pH of the formulation or the skin tissues under theformulation layer to minimize irritation. Preferred non-volatilesolvents are selected from isopropyl myristate and saturatedpolyglycolyzed C8-C10 glycerides or combinations thereof. Preferredcompositions according to the instant invention do not contain glycerolmonooleate.

For most compositions, the weight percentage of the non-volatilesolvent(s) can be from about 2 wt % to about 30 wt %, and morepreferably from about 2 wt % to about 20 wt %, based on the total weightof the composition.

The selection of the solidifying agent can also be carried out inconsideration of the other components present in the topicalpharmaceutical composition. An appropriate solidifying agent iscompatible with the composition such that the composition is in liquidor semi-liquid state, e.g. cream, paste, gel, ointment, etc., before anyevaporation of the volatile solvent(s) and becomes a soft, coherentsolid after the evaporation of at least some of the volatile solvent(s).The solidifying agent can be selected or formulated to be compatiblewith the antibiotic and the solvent vehicle (including the volatilesolvent(s) and the non-volatile solvent(s), as the case may be), as wellas provide desired physical properties to the solidified layer once itis formed. Depending on the antibiotic, solvent vehicle, and/or othercomponents that may be present, the solidifying agent can be selectedfrom a variety of agents. In one embodiment, the solidifying agent caninclude polyvinyl alcohol with a MW range of 20,000-70,000 (Amresco),esters of polyvinylmethylether/maleic anhydride copolymer (ISP GantrezES-425 and Gantrez ES-225) with a MW range of 80,000-160,000, neutralcopolymer of butyl methacrylate and methyl methacrylate (degussaPlastoid B) with a MW range of 120,000-180,000, dimethylaminoethylmethacrylate-butyl methacrylate-methyl methacrylate copolymer (degussaEudragit E100) with a MW range of 100,000-200,000, ethyl acrylate-methylmethacrylate-trimethylammonioethyl methacrylate chloride copolymer witha MW greater than 5,000 or similar MW to Eudragit RLPO (Degussa), Zein(prolamine) with a MW greater than 5,000 (Zein, MW around 35,000,Freeman industries), pregelatinized starch having a MW similar toInstant Pure-Cote B793 (Grain Processing Corporation), ethyl cellulosewith a MW greater than 5,000 or a MW similar to Aqualon EC N7, N10, N14,N22, N50, or N100 (Hercules), fish gelatin having a MW range of20,000-250,000 (Norland Products), gelatin, other animal sources with aMW range greater than 5,000, acrylates/octyl-acrylamide copolymer with aMW range greater than 5,000 or a MW similar to National Starch andChemical Dermacryl 79.

In another embodiment, the solidifying agent can include ethylcellulose, hydroxy ethyl cellulose, hydroxy methyl cellulose, hydroxypropyl cellulose, hydroxypropyl methyl cellulose, carboxymethylcellulose, methyl cellulose, polyether amides, corn starch,pregelatinized corn starch, polyether amides, shellac, polyvinylpyrrolidone, polyisobutylene rubber, polyvinyl acetate phthalate, orcombinations thereof. In a further embodiment, the solidifying agent caninclude ammonia methacrylate, carrageenan, cellulose acetate phthalateaqueous such as CAPNF from Eastman, carboxy polymethylene, celluloseacetate (microcrystalline), cellulose polymers, divinyl benzene styrene,ethylene vinyl acetate, silicone, guar gum, guar rosin, gluten, casein,calcium caseinate, ammonium caseinate, sodium caseinate, potassiumcaseinate, methyl acrylate, microcrystailine wax, polyvinyl acetate, PVPethyl cellulose, acrylate, PEG/PVP, xantham gum, trimethylsiloxysilicate, maleic acid/anhydride colymers, polacrilin, poloxamer,polyethylene oxide, poly glactic acid/poly-l-lactic acid, turpene resin,locust bean gum, acrylic copolymers, polyurethane dispersions, dextrin,polyvinyl alcohol-polyethylene glycol co-polymers, methyacrylicacid-ethyl acrylate copolymers such as BASF's Kollicoat polymers,methacrylic acid and methacrylate based polymers such aspoly(methacrylic acid), or combinations thereof. In yet a furtherembodiment, the solidifying agent can include a combination ofsolidifying agents set forth in the any of the above discussedembodiments. Other polymers may also be suitable as the solidifyingagent, depending on the solvent vehicle components, the drug, and thespecific functional requirements of the given formulation.

In one embodiment of the present invention, the solidifying agentincludes a methacrylic polymer or copolymer such as methyacrylicacid-ethyl acrylate copolymer, butyl and methyl methacrylate copolymer,aminoalkyl methacrylate copolymer, and/or an ammonioalkyl methacrylatecopolymer. In another embodiment, the solidifying agent includespolyvinyl alcohol or a polyvinyl alcohol copolymer such as polyvinylalcohol-polyethylene glycol copolymer.

Preferred solidifying agents are selected from hydroxy propyl cellulose,ammonia methacrylate and acrylates/octylacrylamide copolymer.

For most compositions, the weight percentage of the solidifying agent(s)can be from about 5 wt % to about 60 wt %, and more preferably fromabout 5 wt % to about 40 wt %, based on the total weight of thecomposition.

The non-volatile solvent system and the solidifying agent are preferablycompatible with one other. Compatibility can be defined as i) thesolidifying agent does not substantially negatively influence thefunction of the non-volatile solvent system; ii) the solidifying agentcan hold the non-volatile solvent system in the solidified layer so thatsubstantially no non-volatile solvent oozes out of the layer, and iii)the solidified layer formed with the selected non-volatile solventsystem and the solidifying agent has acceptable flexibility, rigidity,tensile strength, elasticity, and adhesiveness. The weight ratio of thenon-volatile solvent system to the solidifying agent can be from about0.01:1 to about 100:1, or more preferably from about 0.05:1 to about40:1. In some embodiments, the non-volatile solvent system makes upabout 20-60% of the total weight of the formulation.

The thickness of the topical pharmaceutical composition layer applied onthe skin should also be appropriate for a given formulation and desiredantibiotic delivery considerations. If the layer is too thin, the amountof the antibiotic may not be sufficient to support sustained deliveryover the desired length of time. If the layer is too thick, it may taketoo long to form a non-messy outer surface of the solidified layer. Ifthe antibiotic is very potent and the solidified layer has very hightensile strength, a layer as thin as 0.01 mm may be sufficient. If theantibiotic has rather low potency and the solidified layer has lowtensile strength, a layer as thick as 2-3 mm may be desirable. Thus, formost antibiotics and compositions, the appropriate thickness can be fromabout 0.01 mm to about 3 mm, 0.1 mm to about 2 mm, or from about 0.2 mmto about 0.4 mm. In one embodiment, the compositions of the presentinvention can have sufficient gas volatile solvents such that theformulation can be contained in a pressurized container and applied tothe skin by spraying.

In a further embodiment the compositions may also include various agentsand ingredients commonly employed in dermatological or cosmeticcompositions such as perfumes, coloring agents and antioxidants.

Preferred compositions are:

Substance Amount Source Azithromycine 1-7 g Chemos GmbHHydroxypropylcellulose (Type MF EP) 0.5-1 g — MIGLYOL 812 (medium chain1-2 g Hüls AG triglycerides) Octylacrylamide Copolymer 1-2 g NationalStarch (DERMACRYL 79) CAS 129702-02-9 Ethanol 94% ad 30 g —

In view of the findings that the spirochetal form of Borreliaburgdorferi is the prevailing form at the early infection stage and saidform has a high metabolic activity, it is preferred to apply the topicalpharmaceutical composition as short as possible, preferably less thanone day and more preferably less than two days, after the tick bite.However, the instant topical pharmaceutical compositions allow for avery good penetration of the antibiotic into intracellular andinterstitial tissue compartments eradicating also the cystic andspherical forms of Borrelia burgdorferi and thus offer a high rate ofsuccessful prevention even if applied up to 7 days, preferably up to 5days, after the tick bite. These findings may be translated in a dosageregimen whereby the topical pharmaceutical composition is applied to thesite of the tick bite up to 7 days after the tick bite at least once aday for a period of at least 4 days. Preferred are dosage regimenswhereby the topical pharmaceutical composition is applied to the site ofthe tick bite up to 5 days after the tick bite. Further preferred aredosage regimens whereby the topical pharmaceutical composition isapplied to the site of the tick bite at least twice a day.

Further preferred are dosage regimens whereby the topical pharmaceuticalcomposition is applied to the site of the tick bite for a period of atleast 3 days.

Concentrations, amounts, and other numerical data may be expressed orpresented herein in a range format. It is to be understood that such arange format is used merely for convenience and brevity and thus shouldbe interpreted flexibly to include not only the numerical valuesexplicitly recited as the limits of the range, but also to include allthe individual numerical values or sub-ranges encompassed within thatrange as if each numerical value and sub-range is explicitly recited. Asan illustration, a numerical range of “about 0.01 to 2.0 mm” should beinterpreted to include not only the explicitly recited values of about0.01 mm to about 2.0 mm, but also include individual values andsub-ranges within the indicated range.

EXAMPLES

The following examples illustrate the embodiments of the invention thatare presently best known. However, it is to be understood that thefollowing are only exemplary or illustrative of the application of theprinciples of the present invention. Numerous modifications andalternative compositions, methods, and systems may be devised by thoseskilled in the art without departing from the spirit and scope of thepresent invention. The appended claims are intended to cover suchmodifications and arrangements. Thus, while the present invention hasbeen described above with particularity, the following examples providefurther detail in connection with what are presently deemed to be themost practical and preferred embodiments of the invention.

Composition A

Composition [mg] Component per unit [1 g] Function Erythromycin base 150antibiotic Isopropyl myristate 40 non-volatile solvent Glyceroltriacetate 40 non-volatile solvent Butylhydroxytoluene 0.4 antioxidantAmmonia methacrylat, pure 300 solidifying agent Water purified 75volatile solvent Ethanol 94% ad 1 g volatile solvent

Composition B

Composition [mg] Component per unit [1 g] Erythromycin base 150DERMACRYL 79 50 (acrylate/acrylamide copolymer) KLUCEL MF (hydroxypropylcellulose) 25 MIGLYOL 812 (medium chain triglycerides) 50 Ethanol 94%(w/w) ad 1 g

Composition C

Composition [mg] Component per unit [1 g] Azithromycin 150 DERMACRYL 7950 (acrylate/acrylamide copolymer) KLUCEL MF (hydroxypropyl cellulose)25 MIGLYOL 812 (medium chain triglycerides) 50 Ethanol 94% (w/w) ad 1 g

One possibility to demonstrate the successful prevention of Lyme diseaseby topical application of an antibiotic is described in the followinganimal model.

Spirochetes:

Low-passage (passage 4) B. burgdorferi sensu stricto N40 organisms thatare infective for mice (Barthold, S. W. et al., Lyme borreliosis inselected strains and ages of laboratory mice, J. Inf. Dis., 1990, 162,p. 133-138) are used in this study. Spirochetes are cultured in modifiedBarbour-Stoenner-Kelly (BSK II) medium containing Kanamycin (0.8 JII/ml,Sigma, Steinheim, Germany) and Rifampicin (50 μg/ml, Sigma) at 33° C.

Mice:

C3H1HeN (C3H) mice are bred and maintained in individually ventilatedcaging units (Ehret, Berlin, Germany). C57BU6 RAG1-f-(RAG rf) mice arepurchased from the Bundesinstitut für Risikobewertung (Berlin, Germany).Mice are kept under specific pathogen-free conditions in the animalfacility at the Institute of Immunology, College of Veterinary Medicine,University of Leipzig, and in accordance with the guidelines approved bythe Animal Care and Usage Committee of the Regierungs-präsidium Leipzig,Germany.

Host-Adapted B. burgdorferi s.s:

Forty pathogen-free RAGrl-mice are infected by intradermal injectioninto the shaven backs with 10⁶ B. burgdorferi s.s. organisms. Mice aresacrificed by C0₂ asphyxiation 7 days post inoculation and heart bloodis collected aseptically and pooled. EDTA (0.16%) is added asanticoagulant.

Intradermal Injection of B. burgdorferi s.s. into Mice:

Two groups of C3H mice are each inoculated intradermally into the shavenback with 100 μl of the pooled blood from RAG-f-mice containinghost-adapted B. burgdorferi (the inocula of 100 μl is divided in twoadjoining injections).

Application of antibiotic: At days 1, 2 and 3 after the injection, theantibiotic formulated as shown for Composition A or B, respectively, isapplied at the injection area.

At day 56 post inoculation mice are sacrificed for subsequent analysis.

Detection of B. burgdorferi s.s. in Tissue Samples by Culture:

Aseptically collected tissue samples from the heart, urinary bladder,tarsus and ear are squashed in 200 μl BSK II medium. Tissue homogenatesare transferred into 12-ml screw cap tubes containing 6 ml BSK IImedium. Cultures are incubated at 33° C. for 6 weeks and examined weeklyfor spirochetes by dark-field microscopy.

ELISA and Western Blots:

Serum samples of mice collected during necropsy are tested for B.burgdorferi-specific antibodies. A computerized kinetic ELISA (KELA) andimmunoblot analyses are performed as described by Appel, M. J. G. etal., Experimental Lyme disease in dogs produces arthritis and persistentinfection, J. Inf. Dis., 1993, 167, p. 651-664. Sonicated whole B.burgdorferi N40 lysate is used as antigen in both tests. Murine B.burgdorferi-specific antibodies are detected with goat-anti-mouseimmunoglobulin G conjugated to horseradish peroxidase (R&D Systems,Minneapolis, USA). The C₆ antigen-specific ELISA is performed with theQuantitative Lyme C₆ Antibody Test Kit (IDEXX GmbH, Ludwigsburg,Germany).

Results:

Samples taken from the group of mice having been treated with thetopical antibiotic composition A or B, respectively, show a significantreduction in infection of Lyme disease compared to the control group.

In a variation of above described study and instead of transdermalinjection of B. burgdorferi s.s. into mice, the infection can be done byB. burgdorferi s.s infected ticks. B. burgdorferi carrying ticks aretypically allowed to feed from mice for 5 days before the ticks areremoved and the site of feeding is treated with Formulation C. Typically75 mg formulation C is applied to the site of tick-feed covering a skindiameter of 1.5 cm in diameter, corresponding to approx. 15 mgAzithromycine per day and mouse. Treatment is initiated right afterremoval of the tick and continues the following 2 days (24 hour intervalbetween each treatment) for a total of 3 treatments.

Results:

There is no infection of Lyme disease detectable when composition C isapplied to the area where the ticks were allowed to feed. The topicalapplication of Formulation C results in antibody titers, which are notdifferent from naïve mice (KELA values between 10 and 40), whereas theinfected mice show KELA values of 160 to 400.

Especially, the tissue and serum samples taken from different parts ofthe mice 56 days after the tick bite show no Borrelia burgdorferiorganisms when cultivated and no specific antigenes are detectable.Tissue probes are taken from heart tissue, bladder, joint and ear. Thegroup of mice topically treated with Formulation C show complete absenceof B. burgdorferi, whereas B. burgdorferi is detected in untreated mice,which are exposed to tick-feed.

The recultivation conditions of B. burgdorferi are suitable to detect B.burgdorferi in any morphological form known to date. Surprisingly,Formulation C was able to eradicate B. burgdorferi in a way, that noinfectious agents of B. burgdorferi are detected in the target tissuesof B. burgdorferi.

The invention claimed is:
 1. A method for preventing Lyme disease or forthe elimination of spirochetal, cystic and/or spherical forms ofBorrelia burgdorferi resulting from a tick bite on a patient, comprisingadministering to the site of the tick bite a therapeutically effectiveamount of a topical pharmaceutical composition comprising azithromycin,a solvent with greater volatility than water, a solvent less volatilethan water, and a solidifying agent.